ECOSTRESS water use efficiency (WUE) layer from ECO_L4T_WUE product, acquired over Texas, United States, on October 21, 2023.
View full-size imageThe ECOsystem Spaceborne Thermal Radiometer Experiment on Space Station (ECOSTRESS) mission measures the temperature of plants to better understand how much water plants need and how they respond to stress. ECOSTRESS is attached to the International Space Station (ISS) and collects data globally between 52° N and 52° S latitudes. A map of the acquisition coverage can be found on the ECOSTRESS website.
The ECOSTRESS Tiled Water Use Efficiency Instantaneous L4 Global 70 m (ECO_L4T_WUE) Version 2 data product provides Water Use Efficiency (WUE) data generated by dividing the Breathing Earth System Simulator (BESS) Gross Primary Production (GPP) by the Priestley-Taylor Jet Propulsion Laboratory Soil Moisture (PT-JPL-SM) transpiration to estimate WUE, the ratio of grams of carbon that plants absorb to kilograms of water that plants release. The product provides a BESS GPP estimate that represents the amount of carbon surrounding the plants.
The ECO_L4T_WUE Version 2 data product is available globally in Cloud Optimized GeoTIFF (COG) format and uses a modified version of the Military Grid Reference System (MGRS), which divides Universal Transverse Mercator (UTM) zones into square tiles that are 109.8 km by 109.8 km with a 70 meter (m) spatial resolution. Each granule contains separate COG files for each layer: Water Use Efficiency (WUE), Water Gross Primary Production, cloud mask, and water mask. A low-resolution browse is also available showing WUE as a stretched image with a color ramp in JPEG format.
| Characteristic | Description |
|---|---|
| Collection | ECOSTRESS |
| DOI | 10.5067/ECOSTRESS/ECO_L4T_WUE.002 |
| File Size | ~4 MB |
| Temporal Resolution | Varies |
| Temporal Extent | 2018-07-09 to Present |
| Spatial Extent | Global (+/- 52 degrees latitude) |
| Coordinate System | Universal Transverse Mercator (UTM) |
| Datum | World Geodetic System (WGS84) |
| File Format | Cloud Optimized GeoTIFF (COG) |
| Geographic Dimensions | 109.8 km x 109.8 km |
| Characteristic | Description |
|---|---|
| Number of Science Dataset (SDS) Layers | 4 |
| Columns/Rows | 1568 x 1568 |
| Pixel Size | 70 m |
| SDS Name | Description | Units | Data Type | Fill Value | No Data Value | Valid Range | Scale Factor |
|---|---|---|---|---|---|---|---|
| WUE | Water Use Efficiency | g C kg⁻¹ H₂0 | 32-bit floating point | NaN | N/A | N/A | N/A |
| GPP | Gross Primary Productivity | μmol m⁻² s⁻¹ | 32-bit floating point | NaN | N/A | N/A | N/A |
| cloud | Cloud Mask | N/A | 8-bit unsigned integer | 255 | N/A | 0, 1 | N/A |
| water | Water Mask | N/A | 8-bit unsigned integer | 255 | N/A | 0, 1 | N/A |
| Class | Description |
|---|---|
| 0 | Clear |
| 1 | Cloudy |
| Class | Description |
|---|---|
| 0 | Land |
| 1 | Water |
Quality information for the ECO_L4T_WUE Version 2 data product is described in Section 5 of the ATBD.
Data acquisition gap: ECOSTRESS was launched on June 29, 2018, and moved to autonomous science operations on August 20, 2018, following a successful in-orbit checkout period. On September 29, 2018, ECOSTRESS experienced an anomaly with its primary mass storage unit (MSU). ECOSTRESS has a primary and secondary MSU (A and B). On December 5, 2018, the instrument was switched to the secondary MSU, and science operations resumed. On March 14, 2019, the secondary MSU experienced a similar anomaly, temporarily halting science acquisitions. On May 15, 2019, a new data acquisition approach was implemented, and science acquisitions resumed. To optimize the new acquisition approach, only Thermal Infrared (TIR) bands 2, 4, and 5 are being downloaded. The data products are the same as before, but the bands not downloaded contain fill values (L1 radiance and L2 emissivity). This approach was implemented from May 15, 2019, through April 28, 2023.
Data acquisition gap: From February 8 to February 16, 2020, an ECOSTRESS instrument issue resulted in a data anomaly that created striping in band 4 (10.5 micron). These data products have been reprocessed and are available for download. No ECOSTRESS data were acquired on February 17, 2020, due to the instrument being in SAFEHOLD. Data acquired following the anomaly have not been affected.
Data acquisition: ECOSTRESS has now successfully returned to 5-band mode after being in 3-band mode since 2019. This feature was successfully enabled following a Data Processing Unit firmware update (version 4.1) to the payload on April 28, 2023. To better balance contiguous science data scene variables, 3-band collection is currently being interleaved with 5-band acquisitions over the orbital day/night periods.